1. Field of the Invention
The present invention relates to a filter characteristics changing device, a filter characteristics changing method, a program, and an electronic instrument for solving unnaturalness occurring at the time of changing filter characteristics.
2. Description of the Related Art
Effect providing devices have been known which provide various effects (sound effects) such as reverb, delay, and echo to musical sound data generated from a sound source of an electronic instrument or the like. For example, Japanese Utility Model Publication No. 01-012320 discloses an effect providing device which separately forms an initial reflection sound acquired by delaying and changing input musical sound data and a reverberation sound generated based on musical sound data divided into a plurality of frequency bands and acquired by synthesizing reverberation signals having different delay change modes for each band, and thereby acquires a reverberation effect close to a natural sound. Also, in recent years, an effect providing device using a DSP (Digital Signal Processor) which performs waveform arithmetic processing at high speeds has been known, and an example of this type of device is disclosed in Japanese Patent No. 3620264.
This effect providing device structured by using a DSP which performs waveform arithmetic processing at high speeds can provide various effects (sound effects) by rewriting a microprogram to be executed and control data. For example, as for reverb known as a reverberation effect, a plurality of reverb types with different reverberation characteristics can be supported. The reverb types herein are types of sound fields of different reverberation characteristics.